Nitramines



United States Patent 3,159,678 NITRAMDIES Milton B. Frankel, Pasadena, and Karl Klager, Monrovia, Califi, assignors to Aerojet-General Corporation, Azusa, Calif., a corporation of Ohio No Drawing. Filed June 13, 1957, Ser. No. 666,276 9 Claims. (Cl. 260-583) This invention relates to new compositions of matter and to their preparation. More particularly, the invention relates to nitramines of the following general formula:

wherein R is a hydrogen, alkyl, or nitroallryl radical; A is an alkylene radical; and R is a hydrogen, nitro, alkyl, or nitroalkyl radical.

The nitramines of this invention react with nitric acid according to the method disclosed in our copending US. patent application Serial No. 666,274, now U.S. Patent 3,098,873, filed concurrently with the present application, to form high energy nitramines such as, 3,6-diazal,1,1,3,6-pentanitroheptane, which are useful as high explosives and can be used in any conventional explosive missile, projectile, rocket, or the like, as the main explosive charge. An example of such a missile is disclosed in United States Patent 2,470,162, issued May 17, 1949. One way of using the high explosives which can be prepared from the nitrarnines of the present invention in a device such as that disclosed in United States Patent No. 2,470,162, is to pack the crystalline explosive in powder form into the warhead of the missile. Alternatively, the crystals can be first pelletized and then packed. A charge thus prepared is sufficiently insensitive to withstand the shock entailed in the ejection of a shell from a gun barrel or from a rocket launching tube under the pressure developed from ignition of a propellant charge, and can .be caused to explode on operation of an impactor time fuse-mechanism firing a detonating explosive such as lead azide or mercury fulrninate.

The novel nitramine compounds of this invention are prepared by condensing nitraza amines with ii-geminal polyrnitro alcohols in accordance with the general reaction scheme set forth below:

No, It N0,

Example I.Pre paration of 3,6-Diaza- 1,1,1,6- Tetranitroheptane To a mixture of 25.5 g. (0.16 mole) of 'l-nitraza-lbutyl ammonium chloride, 29.7 g. (0.16 mole) of 2,2,2-

trinitroethanol and 150ml. of distilled water, was added 50 m1. of water containing 6.7 g. (0.16 mole) of sodium hydroxide in solution. An orange-colored oil formed which was extracted with. tetr-ahydrofuran and subsequently dried and concentrated in vacuo to yield, as the final product, 29 g. (64.3%) of a red oil.

3,159,678 Patented Dec. 1, 1964 Optimum results areobtained from the condensation reaction of this invention when it is carried out at a pH below about 8 and preferably within the range from about 4 to about 8.

7 Reaction temperature is non-critical in the condensation reaction of this invention, the only eliect of temperature variation being a corresponding increase or decrease in reaction rate.

As a matter of convenience, the free nitraza amine starting materials of this invention are preferably generated in situ from their corresponding strong mineral acid salts by neutralizing said strong mineral acid salts with inorganic basic salts, as for example hydroxides or carbonates, or weak organic acid salts, as for example acetates, of alkali or alkaline earth metals as more fully disclosed inassignees copending US. patent application Serial No. 666,273, now US. Patent 3,000,954, filed concurrently with the present application. For reasons of convenience and economy we prefer to use sodium hydroxide as our free nitraza amine generating agent but other suitable agents such as, for example, calcium hydroxide, magnesium hydroxide, sodium carbonate, sodium acetate, etc, can be used for this purpose if desired.

Any of the strong mineral acid salts such as nitric acid, hydrochloric acid, etc., salts of our amine starting materials can be used in the practice of our invention as taught herein.

Nitraza amine salts useful in the practice of this invention are prepared by reacting a corresponding nitraza isocyanate such as, for example, S-nitraza-l-butyl isocyamate, with an aqueous solution of a strong mineral acid, as more fully disclosed in assignees copending US. patent application Serial No. 666,273, now US. Patent 3,000,954, filed concurrently with the present application.

The [r-geminal poly-nitro alcohol reaction of this inventioncan be 2,2-dinitro-l-ethanol; 2,2,2-trinitroethanol; a

compound in which R is an alkyl radical as, for example,

pared by condensing labile hydrogen containing nitro alkanes, such as, trinitromethane, with formaldehyde.

It will be appreciated that a wide variety of compounds 7 can be prepared in accordance with the method of our invention. For example, the strong mineral acid salts of 4-nitraza-1-hexylamine; 3-aza-3,5,5-trinitro-l-hexylamine; and 3-nitraza-l-butylamine react with 2,2-dinitro-lethanol; 2,2-dinitro-l-propanol; and 2,2,4,4-.tetranitro-lbutanol, respectively, to produce 3,7-diaza-1,1,7-trinitrononane; 4,7-diaza-2,2,7,9,9-pentanitrodecane; andv 5, 8-diaza 1,1,3,3,'8 pentaniu'ononane, respectively. 7 Other members of this new series of compounds are prepared simply by reacting appropriate starting materials.

We claim: I 1. As a composition of matter, a nitramine having the general formula: 7

wherein R is an alkyl radical and A is an alkylene radical.

2. As a composition of matter, 3,6-dia21a-1,l,l,6-tetranitroheptane having the structural formula:

3. The method of preparing a nitramine having the general formula:

which comprises condensing a nitraza amine having the general formula:

N RCH I I-RCH NHz with a fi-geminal polynitro alcohol having the general formula:

HO-OH -(l-R wherein R is a radical selected from the group consisting of hydrogen, alkyl, and ni-troalky-l radicals; A is an alkylene radical; and R is a radical selected from the group consisting of hydrogen, nitro, a-lkyl, and nitroalkyl radicals.

4. The method of claim 3 in which the nitraza amine is generated in situ.

5. The method of claim 3 in which the nitraz-a amine is generated in situ from a strong mineral acid salt thereof by neutralizing said salt with an aqueous solution of a salt selected from the group consisting of the inorganic basic salts and the weak organic acid salts of the alkali and alkaline earth metals.

which comprises condensing a nitraza amine having the general formula:

NO; RI T-ANH with 2,2,2-trinitroethanol; wherein R is an alkyl radical and A is an alkylene radical.

7. The method of claim 6 in which the nitraza amine is generated in situ.

8. The method of preparing 3,6-diaza-1,l,1,6-tetranitro heptane which comprises condensing 3-nitr-aza-1-butyl amine with 2,2,2-trinitroethanol.

9. The method of claim 8 in which the 3-n-itraZa-l-butyl amine is generated in situ.

OTHER REFERENCES Textbook of Organic Chemistry, Wertheim, 2nd Ed., The Blakiston Co., Philadelphia, page 308. 

1. AS A COMPOSITION OF MATTER, A NITRAMINE HAVING THE GENERAL FORMULA: 